Jet Engine Deflector

ABSTRACT

A deflector for a jet engine. The deflector may prevent the jet engine from ingesting birds during a bird strike scenario. The deflector may include a series of ribs, spokes, or vanes that may vary in width and/or thickness from fore to aft, and/or may be curvilinear in one or more planes of view, and/or may serve double duty as inlet vanes for redirecting inlet air.

TECHNICAL FIELD

This disclosure relates in general to deflector apparatus and inparticular to deflector apparatus for use with turbine engines such asaircraft power plants and the like.

BACKGROUND

The problems caused by ingestion of foreign objects into the air inletof jet engines have long been recognized in the art. This problem isparticularly acute with jet engines used on aircraft, since such enginesare operated in an environment where foreign objects cannot be removedor controlled. The engines of jet aircraft taxiing on the groundfrequently ingest foreign objects such as tools and other small metalobjects, while a jet aircraft in flight is susceptible to ingestion ofbirds, leaves, paper, and other airborne debris.

The ingestion of almost any solid foreign object into the air inlet of ajet engine causes damage to the compressor stages, and possibly to otherportions of the engine. This engine damage is immediately manifested bya partial or complete loss of available engine thrust, with consequentimpairment of aircraft flying ability.

The problem of bird ingestion into jet engines is particularly acuteduring aircraft take-off, where an aircraft may fly through a flock ofbirds at precisely the time when maximum available thrust is requiredfor a safe take-off. Since many commercial and private jet-poweredaircraft have only two engines, it will be appreciated that a partialloss of power in both engines, or a total loss of power in one engine,occurring during or shortly after take-off can have drasticconsequences. Post-crash investigations have proved that numerous jetaircraft crashes, resulting in loss of life and extensive propertydamage, are directly attributable to bird ingestion which occurredduring or shortly after take-off.

According to FAA statistics, there have been over 100,000 (Civil andUSAF) wildlife strikes between 1990 and 2008, and the number of strikeshas climbed steadily since 1990. In 1990, the industry saw 1,738 birdstrikes; in 2007, the number had increased to 7,666. Some of that trendis due to increased air travel, but the frequency of wildlife strikeshas tripled from 0.527 to 1.751 per 10,000 flights.

Bird strikes, particularly of the jet's engines, can have catastrophicconsequences. On October 4, 1960, Eastern Air Lines Flight 375 wasstruck by a flock of European starlings during take-off. All fourengines were damaged and the aircraft crashed in the Boston harbor.There were 62 fatalities.

Although FAA regulations require that jet engines be designed to permitcontinued operation after ingesting a bird of specified size at aspecified aircraft speed, such design has not eliminated bird strikescausing engine damage and/or failure. On January 15, 2009, a double birdstrike involving Canadian geese impacted U.S. Airways Flight 1549, anAirbus A320-214, about three minutes after take-off from La Guardiaairport, when the airplane was at an altitude of 2,818 feet AGL (aboveground level). The bird strike resulted in an immediate and completeloss of thrust to both engines, forcing the crew to ditch the plane inthe Hudson River.

FAA statistics report that 92% of bird strikes occur at or below 3,000feet AGL, thus at a critical point of takeoff or landing. Proposedground-based wildlife abatement programs, such as radar detection ofbird flocks and use of lights, noise makers, and water cannons are oflittle to no use in abating bird strikes at altitudes such as Flight1549 experienced, or higher altitudes.

The increase in bird strikes has resulted in regular reports ofcommercial jets being forced to make emergency landings shortly aftertakeoff. According to FAA statistics, gulls are the most common type ofbird to strike aircraft, accounting for 19% of the birds identified inbird strikes. Doves and pigeons are the second most common, accountingfor 15% of the birds identified in bird strikes. But as Flight 1549proves, bird strikes of larger birds such as Canada geese can alsooccur, with devastating consequences.

There are many factors contributing to increasing rates of bird strikesby commercial and military aircraft. These factors include: 1) As jettravel replaced the noisier and slower piston-powered aircraft, thechance of these jets colliding with wildlife increased; 2) Along withthe change in mode of travel there has been an increase in air trafficworldwide, both military and commercial; 3) Natural habitat surroundsmany modern airports and this habitat provides shelter, nesting area,and feeding areas for wildlife that is not usually present in thesurrounding metropolitan area; 4) Many of the world's busiest airports,including Washington Reagan National, Philadelphia International, NewYork La Guardia, and Boston Logan International, are near large bodiesof water that create the aforementioned natural habitats for large waterfowl such as geese and ducks; 5) Wildlife conservation measuresgenerally serve to increase the populations of native birds. Thesefactors result in a majority of wildlife strikes occurring within theimmediate airport environment. According to FAA statistics, over $600million dollars annually is lost due to wildlife strikes with civilaircraft in the United States alone.

The term “jet engine” as used herein is intended to include varioustypes of engines which take in air at a relatively low velocity, heatthe air through combustion, and expel the air at a much higher velocity.The term “jet engine” includes turbojet engines and turbofan engines,for example.

A jet engine conventionally comprises a compressor section forcompression of the intake air, a combustion section for combustion ofthe compressed air and a turbine section arranged behind the combustionchamber, the turbine section being rotationally connected to thecompressor section in order to drive this by means of the energy-richgas from the combustion chamber. The compressor section usuallycomprises a low-pressure compressor and a high-pressure compressor. Theturbine section usually comprises a low-pressure turbine and ahigh-pressure turbine. The high-pressure compressor is rotationallylocked to the high-pressure turbine via a first shaft and thelow-pressure compressor is rotationally locked to the low-pressureturbine via a second shaft.

In the aircraft jet engine, stationary guide vane assemblies are used toturn the flow from one angle to another. The stationary guide vaneassembly may be applied in a stator component of a turbo-fan engine at afan outlet, in a Turbine Exhaust Case (TEC) and in an Inter-Mediate Case(IMC).

SUMMARY

According to an embodiment of the disclosure, there may be provided adeflector comprising a plurality of radially disposed spokes, the spokesbeing curvilinear in at least two planes of view.

According to another embodiment of the disclosure, there may be provideda deflector comprising a plurality of radially disposed ribs, spokes, orvanes including a narrower section proximate the forward end of thedeflector, transitioning to a wider section proximate the aft end of thedeflector.

According to another embodiment of the invention, there may be provideda deflector comprising a plurality of radially disposed ribs, spokes, orvanes including a thicker section proximate the forward end of thedeflector, transitioning to a thinner section proximate the aft end ofthe deflector.

According to another embodiment of the invention, there may be provideda deflector comprising a plurality of radially disposed ribs, spokes, orvanes including one or more air inlet holes.

According to another embodiment of the disclosure, there may be provideda jet engine with an air inlet deflector, the air inlet deflectorincluding an attachment ring attached to a structural frame of the jetengine proximate the air inlet thereof; a plurality of curvilinearvanes, each vane being curvilinear in at least two planes of view andconnected at their rearward ends to the attachment ring; and a centralhub positioned at the forward most end of the deflector, each of thecurvilinear vanes being attached to the central hub.

According to another embodiment of the disclosure, there may be provideda method of preventing ingestion of flying debris by an air inlet, themethod comprising mounting a plurality of radially spaced rib membersabout the air inlet; providing adjoining rib members with a maximalspacing that precludes ingestion of flying debris of a predeterminedsize through the maximal spacing; and configuring the rib members so asto turn incoming air from a direction generally normal to the air inletto a direction that is at least partially radial with respect to the airinlet.

These and other features of the present disclosure will become apparentto one of ordinary skill in the art upon review of the followingdetailed description when taken in conjunction with the drawings and theappended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic representation of a frontal view of a deflector ofthe present disclosure.

FIG. 2 is a schematic representation of a side view of a jet enginedeflector system of the present disclosure.

FIG. 3 is an isometric view of a deflector rib, spoke, or vane of thepresent disclosure.

FIGS. 4 A-C are cross sectional views of exemplary deflector rib, spoke,or vane configurations as viewed along broken lines B-B of FIG. 2.

FIG. 5 is a schematic representation of a portion of a front plan viewof another deflector of the present disclosure.

FIG. 6 is a partial frontal view of another deflector of the presentdisclosure.

FIG. 7 is a cross sectional view of a portion of the deflector of FIG. 6taken along broken lines C-C.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

Referring now to FIGS. 1 and 2, there are illustrated embodiments of adeflector of the disclosure, generally 10. As illustrated, the deflector10 may comprise a series of generally radially disposed ribs, spokes, orvanes 12 arranged circumferentially about the inlet 11 of a jet engine,generally 20. The ribs, spokes, or vanes 12 may be arranged about andconnected to a central hub 14.

As further illustrated in FIG. 2, the ribs, spokes, or vanes 12 mayprovide the deflector 10 with an elongated, generally smooth profilethat may present a generally oblique angle θ relative to the directionof air flow into the engine, as illustrated by the arrow A. Theembodiment illustrated in FIG. 2 is highly elongated, and notnecessarily representative of the degree of elongation that would beemployed in actual use, where cost and weight of materials must beminimized wherever feasible. The oblique angle θ makes it more likelythat a bird or other debris striking the deflector 10 will be deflectedaway from the air inlet 11 of the jet engine 20 to which the deflector10 is mounted, and not become lodged or wedged within the air inletopenings 9 between adjacent ribs, spokes, or vanes 12.

The configuration of the ribs, spokes, or vanes 12 illustrated in FIG. 2is elliptical in profile, although other shapes, including conical,parabolic, hyperbolic, semi-oval, semi-spherical, and the like providingan oblique angle θ to the direction of impact/incoming air flow are ofcourse possible as will now be readily apparent to those of ordinaryskill in the art. As illustrated, the ribs, spokes, or vanes 12 may beseparated from each other by a distance that widens slightly fore toaft, but preferably the widest distance D between adjacent ribs, spokes,or vanes 12 is small enough to prevent a large, heavy bird, such as aCanada goose, from getting through to the air inlet 11 upon impact. Thewidest distance D may also be small enough to present birds the size ofa gull or pigeon, the most common birds ingested in bird strikes, frombeing ingested, although modern jet engines are typically designed to beable to handle ingestion of smaller birds.

As illustrated, the ribs, spokes, or vanes 12 may be curvilinear in twoplanes, as represented in FIGS. 1 and 2, which may create a spiralingeffect. This arrangement may beneficially direct the incoming air from adirection that is generally normal to the air inlet, to a generallyspiral direction (i.e., having a rotational component), which may assistin rotating the intake fan and/or compressor and/or turbine to a greaterextent than would occur without the ribs, spokes, or vanes 12 sooriented. Thus, the ribs, spokes, or vanes 12 may act as stationaryinlet air guide vanes, serving double duty as components of a deflector,as well as guide vanes acting as a stator for turning incoming air in adirection contributing to rotation of the fan, compressor(s) and/orturbine(s).

The ribs, spokes, or vanes 12 may vary in width proximate the fore end,generally 52 of the deflector 10 to the aft end generally 56, asillustrated, with the ribs, spokes, or vanes having a narrower fore end13 and wider aft end 15. The use of ribs, spokes, or vanes 12 that widenin the circumferential direction “c” from fore to aft, as illustrated inFIGS. 1 and 2, may reduce or eliminate the need for cross bar supportsbetween ribs, spokes, or vanes 12, or added ribs, spokes, or vanesproximate the wider end of the deflector as it nears the engine inlet11, which supports and/or added ribs, spokes, or vanes may tend toimpede air intake and/or increase drag and/or increase weight of thedeflector and therefore the engine. It may, however, be desirable incertain configurations, particularly for jet engines of larger diameter,to include cross bar supports between adjacent ribs, spokes, or vanes12.

As illustrated in FIG. 2, the ribs, spokes, or vanes 12 may have arelatively thicker region 50 proximate the fore end, generally 52 of thedeflector 10, and may taper to a relatively thinner region 54, proximatethe aft end, generally 56 of the deflector 10. Thus, the ribs, spokes,or vanes 12 may become relatively, generally, or progressively thinnerin the radial direction “r,” from fore to aft.

Such difference in thickness may contribute to minimizing weight of theribs, spokes, or vanes 12, while providing greater thickness andtherefore material and strength in the regions most needed, for example,the regions of the ribs, spokes, or vanes proximate the narrower foreend 13, while providing less thickness and less material at the wideraft end 15 of the ribs, spokes, or vanes 12. Providing greaterthickness, material, and strength in the thicker region 50 may helpmitigate structural damage to the deflector 10 upon impact with birds orother debris, as the fore end 52 of the deflector 10 is more likely toreceive both the initial impact, and receive such an impact at arelatively smaller (i.e., more direct) angle of incidence, θ₁ comparedto the angle of incidence θ₂ proximate the aft end 56 of the deflector10, as illustrated by the arrows in FIG. 2.

As illustrated in FIG. 2, one or more or all of the ribs, spokes, orvanes 12 and/or central hub 14 may be further configured with one ormore air inlet holes 19. Such air inlet holes 19, when applied to theribs, spokes, or vanes 12, may be spaced along the entire lengththereof, or may be positioned proximate the wider aft end 15. The airinlet holes 19 may further improve air intake through the deflector 10to the jet engine, generally 20. The air inlet holes 19 as illustratedin FIG. 2 may be elliptical in shape, and may increase in size fore toaft as illustrated. Of course other shapes for the inlet holes 19, suchas round, square, rectangular, oval, slotted, or combinations of theseand other shapes may be employed. The size of the air inlet holes 19 maybe small enough to preclude ingestion of large birds, such as Canadageese, or even smaller birds, such as pigeons and starlings. In additionto providing more area for air intake, the air inlet holes 19 may reducethe weight of the ribs, spokes, or vanes 12 and/or the central hub 14.

The air inlet holes 19 may include directional side walls 22 thatredirect the air passing along boundary layers near the outer surface 24of the ribs, spokes, vanes, and/or central hub 14 through the holes 19along a desired flow path, e.g., axially in the direction of the fanand/or compressor, or with a rotational component as previouslydiscussed. FIG. 4A illustrates one example of directional side walls 22that may tend to direct air passing through the air inlet hole 19 fromthe outer surface 24 of the rib, spoke, or vane 12 through the air inlethole 19 and along the inner surface 26 of the rib, spoke, or vane 12 asillustrated by the directional arrows. As illustrated, the air inlethole directional side walls 22 may be tapered, which may contribute toimparting a nozzle effect to the air exiting the air inlet holes 19.Although the side walls 22 as illustrated have a generally inwardlytapered conical configuration, other configurations, e.g. cylindrical,or outwardly flaring conical, may also be used, depending on theapplication.

As illustrated, the ribs, spokes, or vanes 12 may be attached to anattachment ring 16. The attachment ring 16, in turn, may be attached tothe frame 17 of a jet engine, generally 20, as illustrated in FIG. 2,using suitable fasteners 21, according to accepted air frame standards.Such fasteners 21 may be equally spaced about the circumference and/orperimeter of the attachment ring 16. Although the fasteners 21illustrated in FIG. 2 may be bolts or screws, other acceptable fastenersknown to those of ordinary skill in the art may be used, and may beconfigured to permit removal of the deflector 10 for engine maintenance.

As illustrated in FIG. 1, the ribs, spokes, or vanes 12 may be connectedto the attachment ring 16 at an attachment point 60 proximate theleading edge 40 and the wider aft end 15. In the embodiment illustrated,the attachment point 60 may be attached to the inner wall 62 of theattachment ring 16. Such an attachment may permit greater air intake inthe region proximate the wider aft end 15 than might be possible if theentire width of the wider aft end 15 is attached to the inner wall 62 ofthe attachment ring 16, as air may flow through the space 70 between theinner wall 62 of the attachment ring and outer end 72 of the spoke orvane 12.

The inner wall 62 of the attachment ring 16 may be sized to align withthe inner wall 65 of the air inlet 11 to the jet engine 20 to which thedeflector 10 is mounted, to further maximize incoming air, and/ormitigate the effect to which the attachment ring 16 may block incomingair. Other attachment configurations are of course possible, includingattaching the wider aft end 15 of the ribs, spokes, or vanes 12 to theinner wall 62 of the attachment ring 16 across the entire width of thewider aft end 15 of the ribs, spokes, or vanes 12, as illustratedschematically in FIG. 6.

Another attachment configuration is illustrated in FIGS. 2 and 6, wherethe ribs, spokes or vanes 12 may be connected to the attachment ring 16proximate the outer wall 64 thereof. As illustrated, the outside orleading edges 40 of the ribs, spokes, or vanes 12 may be attached to theattachment ring 16 such that the leading edges 40 blend aerodynamicallywith the outer wall 64 of the attachment ring 16 and the outer surfaceor cowling 66 of the jet engine 20. In the embodiment illustrated inFIG. 6, the trailing edge 42 and the outboard surface 76 of the ribs,spokes, or vanes 12 may also blend aerodynamically with the outer wall64 of the attachment ring 16 and the outer surface or cowling 66 of thejet engine 20 at the aft end 56 of the deflector 10, which configurationmay be achieved by imparting a slight twist to the rib, spoke, or vane12 proximate the aft end 56.

Here it may be recognized that the portion of the deflector 10 thatresides outboard of the inner wall 65 of the air inlet 11 may havelittle to no negative impact on air intake to the jet engine 20, andindeed may actually contribute to greater air intake, for examplethrough the use of larger air inlet holes 19 proximate the aft end 56,particularly if such air inlet holes have directional side walls 22 todirect airflow inboard of the inner wall 65, as illustrated in FIGS. 2and 6. As there illustrated, the side walls 22 of the air inlet holes 19that are positioned outboard of the inner wall 65 of the air inlet 11may further include a vane member 70 that may extend radially inwardly.This vane member 70, in combination with the directional side wall 22,may cause air to be redirected from a direction substantially normal tothe air inlet 11 but outboard thereof, as represented by arrow A, to adirection with a radial component, thereby directing the air inboard ofthe inner wall 65 so it may be ingested by the air inlet 11, asillustrated by arrow B.

Further, as illustrated in FIGS. 2 and 6, the deflector 10 may includein the air inlet openings 9 between adjoining ribs, spokes, or vanes 12one or more directional vanes 72 to further assist in directing airtoward the air inlet 11. The directional vanes 72 may comprise flat orcurved members. Such directional vanes 72, in addition to providing forredirecting the air in the direction B, may further contribute tostructural integrity of the deflector 10 by serving as a connectorbetween adjoining ribs, spokes, or vanes 12.

The directional vanes 72, as illustrated in FIGS. 6 and 7, may have acurved outboard surface 74 that may blend with and may havesubstantially the same arc or curvature as the outboard surface 76 ofthe ribs, spokes, or vanes 12 to which it is joined at the points ofconnection 78. The directional vanes 72 may further comprise an inboardsurface 79 that may be directed and/or extend inboard of the inner wall65 of the air inlet 11, and may be straight or, as illustrated in FIG.7, curvilinear, and may direct air radially inboard of the inner wall 65of the air inlet 11 toward the air inlet 11. When appropriately sizedand positioned, the combination of directional vanes 72 with vanemembers 70 outboard of the inner wall 65 of the jet engine air inlet 11may cause virtually all air that would, in connection with a jet engine20 having no deflector 10, to strike the outer cowling of the engine andnot reach the air intake 11, to be redirected generally in the directionof arrow B, substantially increasing airflow into the engine 20.

The ribs, spokes, or vanes 12 may, in cross section, be shaped asairfoils or as the guide vanes shown as element 208 of FIG. 2 of U.S.2010/0158684 A1, incorporated in its entirety by reference herein.Whereas the guide vanes 208 of that disclosure, however, are struts thatterminate in an outer ring, the profile of the vanes or spokes of thepresent disclosure may be arcuate or curvilinear, i.e., semi-elliptical,semi-spherical, parabolic, hyperbolic, semi-oval, etc., in shape fromfore to aft, creating the oblique angle previously described. Such anembodiment is illustrated in FIG. 3.

In the embodiment of the disclosure illustrated in FIG. 3, the ribs,spokes, or vanes 12 may have a generally hollow interior region 30,which may serve to reduce the weight of the ribs, spokes, or vanes 12.As further illustrated, the ribs, spokes, or vanes 12 may be shaped witha narrow forward section 32 that widens to a curved aft section 34. Therib, spoke, or vane embodiments of FIG. 3 may be oriented about the jetengine inlet 11 generally like stator vanes, and may create a change intangential velocity of the incoming air, as well as increasing thatvelocity through a nozzle effect caused by proximity of the ribs,spokes, or vanes 12 to adjacent ribs, spokes, or vanes 12. The effect ofthis orientation of the ribs, spokes, or vanes 12 may be to change thedirection of incoming air from a direction generally normal to the airinlet to a direction that is at least partially rotational relative tothe air inlet, thereby providing a change in the tangential momentum ofthe air, causing a torque on the rotor in the direction of rotation. Theribs, spokes, or vanes 12 may also be oriented so as to have an angularpitch in order to improve air intake and/or tangential air velocity.

In another embodiment of the disclosure, the ribs, spokes, or vanes 12are not oriented in a spiral configuration. Rather, the ribs, spokes, orvanes 12 may be curvilinear in only one plane, and thus may appear tohave straight edges when the deflector 10 is viewed from the front, asillustrated schematically in FIG. 5, and may further appear curvilinear,e.g., semi-circular, semi-ellipsoidal, parabolic, hyperbolic, and/orsemi-oval, when the deflector 10 is viewed from the side. Straight ribs,spokes, or vanes 12 such as illustrated in FIG. 5 may also employ arelatively narrow fore section 13 transitioning to a wider aft section15, and/or a relatively thicker region 50 proximate the fore end 52,transitioning to a relatively thinner region 54 proximate the aft end 56of the deflector 10, and may further include one or more air inlet holes19, which may include direction side walls 22, as previously described.

The ribs, spokes, or vanes 12 are not shown to scale, or with theoptimal number of ribs, spokes, or vanes that might be present on a jetengine according to the present disclosure, and the curvatures andproportions shown may be somewhat exaggerated for visual clarity. Itwill now be readily apparent to those of ordinary skill in the art thatthe disclosure may be optimized to minimize weight, and maximize airintake, while maintaining adequate strength of the deflector to resistbird strikes and ingestion of other flying debris.

Whether the ribs, spokes, or vanes 12 are curvilinear in one or twoplanes, it may be advantageous for the ribs, spokes, or vanes to have anaerodynamic and/or airfoil-shaped cross section, similar to that of aturbine blade or a stator, although the ribs, spokes, or vanes may, forexample, be round, oval, square, rectangular, or triangular in crosssection as well. FIGS. 4 A-C represent a few possible, but by no meansonly, aerodynamic and/or airfoil cross sectional shapes of the ribs,spokes, or vanes as taken along the view represented by broken arrowlines B-B of FIG. 2. When such configuration is used, the ribs, spokes,or vanes 12 may include a leading edge 40 and a trailing edge 42designed to permit maximum flow of air around the spoke or vanes 12 andreduce drag, as illustrated by the arrows representing splitting of theairflow around the ribs, spokes, or vanes 12. The ribs, spokes, or vanes12 may be positioned or angled such that the leading edge 40 may bepositioned slightly outboard with respect to the trailing edge 42, asbest seen in FIGS. 1 and 2.

Jets often strike birds at a relatively high velocity associated withtakeoff, e.g. 200 knots calibrated air speed or greater, and the impactof such strikes, in addition to causing catastrophic engine failure, hasbeen known to seriously damage other structures of the plane, forexample, shattering windshields and rupturing the fuselage. Because ofthe speed with which a jet may be traveling upon impact in a birdstrike, and given the potential for striking large birds such as geese,albatross, vultures, ducks, etc., the deflector 10 may be designed tomaximize impact strength while minimizing added weight to the engine.Accordingly, the ribs, spokes, or vanes 12 may be fabricated fromcarbon-fiber composite, or other known material in the aerospaceindustry, including by way of example aluminum, titanium, and alloysthereof, and resin-impregnated Kevlar® fabric or fibers, and the like.

As ballistic materials such as Kevlar® fiber and fabric are sometimesused as an engine wrap to contain turbine blades, preventing them frompuncturing the jet's cabin in a blade-out scenario, the same materialmay be advantageously used in fabricating the deflector 10 and itscomponents as will now be appreciated by those of ordinary skill in theart. As will also now be appreciated, when the ribs, spokes, or vanes 12have a multiple curve configuration, being curvilinear in at least twoplanes, e.g., elliptical in side profile as illustrated in FIG. 2, andspiral in front plan view as illustrated in FIG. 1, such multiple bends,particularly when metal is used, may increase the strength of the ribs,spokes, or vanes 12 relative to those that are merely straight rods orcurvilinear in only one plane.

The ribs, spokes, or vanes 12 may be attached directly to the frame 17of the jet engine, or, particularly in a retrofit scenario, may beattached to an attachment ring 16 using appropriate fasteners or otherattachment methods. When an attachment ring 16 is used, it may befabricated of the same material as the ribs, spokes, or vanes 12, or adifferent material. When the same material is used, e.g., carbon-fibercomposite, the attachment ring 16 may be fabricated as a unitary piecewith the ribs, spokes, or vanes 12 and the central hub 14. Due tomolding constraints, it may be necessary, in order to mold theattachment ring 16, ribs, spokes, or vanes 12, and central hub 14together, to mold the deflector in two or more sections which may thenbe joined together. If the deflector 10 or its various components aremolded, the molding process may create an opportunity to incorporateheating elements within the structures of the deflector 10, such as theribs, spokes, or vanes 12, and/or central hub 14, which heating elementsmay be used for deicing purposes.

If metal, e.g., titanium or an alloy thereof, is used for the ribs,spokes, or vanes 12, central hub 14, and/or attachment ring 16, thecomponents may be connected using known methods such as welding orriveting, or the deflector 10 may be cast as a unitary piece. If metalcomponents are used for the deflector 10, deicing heating elements maybe incorporated within channels or grooves in the various deflectorcomponents or fastened to an outer surface of the components using knowntechniques. The attachment ring 16 may be fastened to the frame of thejet engine with fasteners, 17, such as bolts 21, for ease ofinstallation and removal for engine maintenance.

The central hub 14 may comprise a solid or hollow structure in the shapeof a truncated cone, having a blunt, rounded frontal surface 18 asillustrated in FIG. 2, and may be fabricated of the same material as theribs, spokes, or vanes 12, or a different material. If the deflector 10is fabricated of a moldable material, such as carbon-fiber composite,the ribs, spokes, or vanes 12 and central hub 14 may be molded as asingle unit. If metal is used, the ribs, spokes, or vanes 12 may bewelded or riveted to the central hub 14. The central hub may,particularly in a molded configuration of the deflector 10, merelycomprise the central point of joinder of all of the ribs, spokes, orvanes 12, and thus may not appear as a separate component, and may havea small or even no discernible diameter.

It is appreciated that any deflector 10 placed fore of a jet engineinlet may tend to reduce the volume of air flowing into the inlet, withconsequent loss of engine efficiency, thrust, fuel economy, etc. It may,therefore, be necessary to increase the diameter of the jet engine airintake in order to account for any decrease in air intake associatedwith mounting the deflector 10 to the engine. The configuration astaught by the present disclosure may, however, tend to minimize theamount of air that is deflected from the air inlet, by virtue of theconfiguration of the ribs, spokes, vanes, and/or central hub, the airinlet openings and holes, and the shape and orientation thereof asdisclosed herein.

While the deflector of the present disclosure has been illustratedmounted to a jet engine having a circular air inlet opening, consistentwith many commercial aircraft, it will now be appreciated that thedeflector as described herein may be mounted to jet engines of any inletconfiguration, including without limitation four-sided, D-shaped,triangular, or oval shaped air inlets. The deflector 10 may, in suchapplications, be sized and configured to conform to the shape of the airinlet opening, for example, by configuring the aft end of the ribs,spokes, or vanes to be spaced around the air inlet opening and/or byproviding an attachment ring sized and configured to conform to the sizeand shape of the air inlet opening.

Although the deflector of the present disclosure has been describedprimarily with respect to jet engines for aircraft, it is intended thatthe disclosure and appended claims may apply to other applications,e.g., use of the deflector with gas turbines for power generation, withpropeller engines of aircraft, and generally with any air inlet whereingestion of birds and other airborne debris is to be avoided.

It will now also be appreciated that deflectors such as disclosed hereinmay be modified to be retractable with respect to the jet engines towhich they may be mounted, to permit retraction of the deflector oncethe airplane has reached an altitude above which bird strikes are highlyunlikely, e.g., 10,000 feet AGL or higher. Such retraction may beachieved by disposing the rib, spoke, or vane members within the cowlingof the engine and including a pusher/retractor mechanism that canmotivate the ribs, spokes or vanes into position and retract them into astowed position within the engine cowling. In such embodiment, thecentral hub could be dispensed with, and the ribs, spokes or vanes couldbe designed with fore ends that come close together and optionallyinterconnect upon deployment. Such a retraction mechanism might utilizethe attachment ring as a motivator for the ribs, spokes, or vanes, whichmay be pivotally connected to the attachment ring, and may includeretraction motors, outer hatch doors, and connections such as are knownin the art, e.g., for retracting landing gear, wing features, and thelike. Such a mechanism might further include straight, or in the case ofspiral shaped ribs, spokes, or vanes, spiral grooves within the enginecowling to direct and retain the ribs, spokes, or vanes in the properalignment upon deployment.

This written description uses examples to disclose the invention,including the best mode, and also to enable any person of ordinary skillin the art to practice the invention, including making and using anydevices or systems and performing any incorporated methods. The stepsrecited in the accompanying method claims need not be taken in therecited order, where other orders of conducting the steps to achieve thedesired result would be readily apparent to those of ordinary skill inthe art. The patentable scope of the invention is defined by the claims,and may include other examples that occur to those of ordinary skill inthe art. Such other examples are intended to be within the scope of theclaims if they have structural elements that do not differ from theliteral language of the claims or if they include equivalent structuralelements with insubstantial differences from the literal languages ofthe claims.

1. A deflector comprising a plurality of radially disposed spokes, saidspokes being curvilinear in at least two planes of view, wherein saiddeflector is generally elongated, having a fore section and an aftsection, and at least one of said spokes gradually increases in widthfrom said fore section to said aft section.
 2. The deflector of claim 1,wherein said spokes are curvilinear in a side plan view and a front planview of said deflector.
 3. The deflector of claim 1 wherein said spokesare joined at their forward end by a central hub.
 4. (canceled)
 5. Thedeflector of claim 1 wherein each said spoke is connected at itsrearward end to an attachment ring.
 6. (canceled)
 7. (canceled)
 8. Thedeflector of claim 32 wherein each of said air inlet openings includes adirectional side wall.
 9. The deflector of claim 1 wherein each saidspoke has an aerodynamic cross section. 10.-16. (canceled)
 17. A birdstrike deflector for a jet engine comprising a plurality of ribs, eachsaid rib gradually increasing in width from fore to aft; a centrallydisposed hub to which each of said ribs is connected at its forward end;and an attachment member to which each of said ribs is connected at itsrearward end.
 18. The bird strike deflector of claim 17 wherein saidribs are each curvilinear in at least two planes of view.
 19. The birdstrike deflector of claim 18 wherein each said curvilinear rib and saidcentrally disposed hub includes one or more air inlet openings.
 20. Thebird strike deflector of claim 19 wherein said air inlet openingsdisposed in said curvilinear ribs increase in size from fore to aft, andat least one said air inlet opening in each rib comprises a directionalside wall and a vane member extending inboard of said air inlet opening,and wherein said bird strike deflector further comprises at least onedirectional vane between adjoining ribs.
 21. A deflector comprising aplurality of radially disposed rib members, each said rib memberincluding a narrower forward section that transitions to a wider aftsection, each said rib member further including a thickness in theradial direction that transitions from a thicker fore section to athinner aft section.
 22. The deflector of claim 21 wherein each said ribmember includes one of more air inlet openings through an outer surfaceof said rib member to an inner surface of said rib member.
 23. Thedeflector of claim 21 wherein each said rib member has a curvilinearcontour when viewed in a side plan view thereof, said curvilinearcontour selected from the group comprising semi-circular,semi-ellipsoidal, parabolic, hyperbolic, and semi-oval.
 24. Thedeflector of claim 23 wherein each said rib member has a curvilinearcontour when viewed from a front plan view thereof.
 25. A method ofpreventing ingestion of flying debris by an air inlet, said methodcomprising: mounting a plurality of radially spaced rib members aboutsaid air inlet; providing adjoining said rib members with a maximalspacing that precludes ingestion of flying debris of a predeterminedsize through said maximal spacing; and configuring said rib members soas to turn incoming air from a direction generally normal to said airinlet to a direction that is at least partially rotational with respectto said air inlet; and providing said rib members with a narrower regionproximate the forward end thereof transitioning to a wider regionproximate the aft end thereof; and providing said rib members with athickness that transitions from a thicker region proximate the forwardend thereof to a thinner region proximate the aft end thereof.
 26. Themethod of claim 25 wherein said rib members are curvilinear.
 27. Themethod of claim 26 wherein said rib members are curvilinear in at leasttwo planes of view.
 28. The method of claim 27 further comprisingproviding a centrally disposed hub to which said rib members areattached at their forward ends.
 29. The method of claim 28 furthercomprising providing one or more air inlet openings in each of said ribmembers and said centrally disposed hub.
 30. (canceled)
 31. (canceled)32. A deflector comprising a plurality of radially disposed spokes, saidspokes being curvilinear in at least two planes of view, wherein eachsaid spoke includes one or more air inlet openings, said air inletopenings increase in size from fore to aft.